Current computer systems store data in files. A stored data collection is often called a document. A document may comprise many different types of data formats, such as text, bitmaps, hypertext links, and other types of data. For example, a document created by a word processing program may comprise text and one or more images. Current systems provide mechanisms for incorporating images into documents for storage and retrieval by various user programs such as word processing, spreadsheet, and web browser programs, among others. The text and image portions of the document are stored together as a single main document.
Because images stored as bitmaps require a large amount of data, storing images with a document causes the main document to be voluminous. If multiple documents refer to the same image, then the system stores multiple copies of the same image, resulting in an unnecessary use of disk space. Accordingly, to reduce disk space required to store a document with an image incorporated therein, some current programs enable a user to use a link to select the image to insert in a main document. The link is then stored with the document, reducing the size of the document.
Current systems also enable an image that is referenced in a document to be changed. In order for those changes to be reflected in an open document, some current systems incorporate a program into the document that runs whenever the document is opened. That program then looks at the referenced image and updates the image within the document whenever the image is changed. The incorporation of such a program into the document again causes that document to be large and requires a great amount of disk space.
Additionally, current systems insert images and other objects into documents as a separate block of data. That inserted block of data is treated like a character. There are drawbacks to this treatment of images and other inserted objects into documents.
Other drawbacks also exist with current systems.